1. Field of the Invention
The present invention relates to a display control apparatus and control method thereof.
2. Description of the Related Art
Some display control apparatus for a personal computer (PC) and the like can set a region on the display screen of the display in accordance with an instruction from an input device such as a pointing device (PD). The set region is used as a processing target subjected to subsequent processing. For example, when a region containing part of an image to be edited is set while the PC executes an image editing application, an image within the region undergoes image processing such as trimming processing.
The region is set by a manipulation of, for example, selecting a start point on the display screen by the user of the display control apparatus with the PD, and moving the pointer from the start point to the end point. In this case, the set region is, for example, a rectangle whose diagonal is defined by the start and end points.
After setting the region, the user may sometimes wants to perform adjustments such as enlargement, reduction, and movement of a region. As a technique regarding a PD manipulation for these adjustments, there is known Japanese Patent Laid-Open No. 6-103013 that discloses a technique concerning enlargement, reduction, and movement of a window. In Japanese Patent Laid-Open No. 6-103013, enlargement of a window or the like is executed by, for example, moving the pointer to contact or cross the boundary of the window. This facilitates the manipulation because the user need not position the pointer to the narrow region of the boundary such as the frame or corner of the window.
In another case, the user may want to delete a set region and set a new region, instead of executing the foregoing adjustment. However, when the technique in Japanese Patent Laid-Open No. 6-103013 is adopted, even if the user designates a position other than a set region with the PD, the set region is adjusted. Hence, before performing the manipulation for setting a region, the user needs to execute any additional manipulation (for example, a manipulation of selecting a set region and pressing a region delete button displayed on the display screen). This additional manipulation increases the manipulation burden on the user.